Our invention relates to a data transfer apparatus for use with disklike record media such as, typically, a flexible magnetic disk now commonly referred to as floppy disks. More specifically our invention pertains to such an apparatus featuring provisions for loading and clamping a record medium in position therein for subsequent data transfer.
Flexible magnetic disks have found widespread acceptance in information processing and allied industries as compact data storage media. Being thin and limply flexible, the disks are usually enclosed in more rigid, apertured envelopes to make up disk assemblies or cartridges that are self supporting.
A problem has arisen in the use of such magnetic disk cartridges as each cartridge is manually inserted in the data transfer apparatus. The apparatus commonly employs a centering cone or collet movable, through the central aperture in the disk that has been loaded in the apparatus, into and out of engagement in a socket in a drive hub which is coupled to a drive motor. Thus captured between cone and hub, the disk rotates therewith for data transfer with a transducer head or heads. The disk cartridge does not, however, come to a position of exact axial alignment with the motor driven hub on being manually inserted in the apparatus through the entrance slot defined therein. If the disk is placed too much out of alignment with the drive hub, the centering cone becomes unable to center the disk, possibly pushing its inner edge portion into the hub socket and so ruining the disk.
Designed to overcome this problem is the U.S. patent application Ser. No. 434,400 filed on Oct. 14, 1982, by Noda, one of the instant inventors. That application suggested the use of a disk loading handle or knob to be manipulated for pushing the incompletely inserted disk cartridge fully into the entrance slot and for activating the centering cone into engagement in the drive hub socket through the central aperture in the disk. This device has proved to have a weakness, however. As the manipulation of the handle results in the movement of the centering cone into engagement in the drive hub socket at the same time with the pushing of the disk cartridge into the entrance slot by the handle, there has been the possibility, if all the related parts are not in good working order, of the centering cone clamping the disk before the complete loading of the cartridge in the apparatus by the handle. The centering cone may then interfere with, or even destroy, the disk cartridge being loaded.